UPD75312B Datasheet, PDF (45/77 Pages) NEC – 4-BIT SINGLE-CHIP MICROCOMPUTER

µPD75312B, 75316B
Caution:
When the main system clock oscillator or subsystem clock oscillator is used, the shaded area in the
figures should be wired as follows to prevent influence from the wiring capacitance, etc.
• Wiring should be as short as possible.
• Do not cross signal lines.
• Do not place the circuit close to a line in which varying high current flows.
• The connecting point of oscillator capacitor should always be the same potential as VDD. Do not connect
it to the power supply pattern in which high current flows.
• Do not fetch a signal from the oscillator.
When the subsystem clock is used, special care is needed for the wiring. The subsystem clock oscillator
is designed to be low-amplification circuit for low current consumption, thus mulfunction due to noise
occurs more often than with the main system clock oscillator.
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